Mozilla has finally released Firefox 4 Mobile for Android and Maemo (Nokia N900). You probably already know all the new features since Firefox 4 Mobile has been in alpha/beta for quite some time, but I'll do a small recap:

Probably the coolest feature is Sync which you can use to sync your Firefox preferences, history, bookmarks, passwords and even tabs across other devices (including your desktop). Sync even supports custom servers.

Extension support

Lots of mobile optimizations are also available in the latest Firefox 4 mobile: pinch to zoom, resize text to fit the screen, volume rocker on Nokia N900

Save to PDF lets you save sites for offline viewing which is quite cool at times.

You can watch the official Firefox 4 Mobile for Android presentation video below:

Overall, Firefox 4 feels quite fast while browsing but the startup time really needs to be improved. It has improved lately but it's still nowhere near as fast as the stock Android browser. I almost dare to say it sometimes makes me forget why I like it - which is mainly thanks to the extensions support.

And speaking of extensions: there are a lot of extensions available already, but of course some of your favourites will probably be missing. For instance, while LastPass shows up in the extensions list, its page says it can't be installed on Android (you can install it from the LastPass website though - but it's not free). Luckily, 2 extensions which I'm sure you like: Adblock Plus and NoScript are already available on the Firefox Mobile addons page.

The CSS3 support is a very nice addition which I've missed in the default Android browser (yes, some people want the web to look nice too). And there's also HTML5 support meaning you can watch YouTube and others without Flash.